Z-touch: A multi-touch system for detecting spatial gestures near the tabletop

Z-touch is a multi-touch table that can detect spatial
hand gestures near the tabletop surface. This system uses a combination
of a multilayered infrared (IR) laser plane and a high-speed
camera. Multilayered IR line laser modules are synchronized with the shutter signal of the high-speed camera. This system allows user interaction on the basis of the posture of the user’s fingers near the tabletop surface without the use of special markers or devices on the fingers.